Right and left valves subequal
and comprising mirror images of one another except for hinge structures

inequivalve

Opposite valves dissimilar
in size or shape or both

prosogyral

Beaks directed forward

opisthogyral

Beaks turned backward instead of projecting forward

In this case, you use the fact that the beak is closer to the anterior
rather than the fact that the beak points to the posterior of this shell.
This is a picture of the left valve, not the right valve.

taxodont

Characterized by more or
less numerous subequal hinge teeth, generally arranged in a row

mytiliform

Slipper-shaped

auriculate

Shell possessing auricles;
equivalent to alate

produced

Shell much elongated in one direction

prosocline

Having forward obliquity, approach to beak along
mid-line of shell inclined forward